This invention relates to perfluoroalkyl-modified polyethyleneimines, more particularly to water soluble poly-perfluoroalkyl-(allyloxy/iodopropyloxy)- or poly-perfluoroalkyl-fluoroallyl-substituted polyethyleneimines which are useful as oil repellents for substrates such as textiles and paper and as foam stabilizers in Alcohol Resistant-Aqueous Fire-Fighting Foam (AR-AFFF) formulations.
Aqueous Fire-Fighting Foam (AFFF) formulations contain water-soluble fluorosurfactants along with hydrocarbon surfactants. They are effective in extinguishing non-polar solvent fires. When an AFFF formulation comes in contact with a burning hydrocarbon fuel, the water, which contains both fluoro- and hydrocarbon surfactants, drains from the foam and forms a thin film on top of the burning fuel. This film does not sink, but due to its low surface energy ( less than 18 dynes/cm, which is lower than that of heptane), it spontaneously spreads across the surface of the burning fuel. There it acts as a vapor suppressant and, in combination with the aqueous foam, extinguishes the fire and prevents reignition of the fuel. It is important in this application that the foam have a long foam life on the hot fuel; otherwise the fuel can reignite, an event called burnback. A long foam life which provides burnback resistance is achieved by having a foam which is xe2x80x9cwetxe2x80x9d, that is hydrated, and from which water can drain down onto the surface and replenish the seal. On a non-polar fuel like gasoline, this task is simple, since water and the water-soluble surfactants are not soluble in the fuel.
This task is considerably more difficult on polar fuels like isopropanol and acetone. Besides the fluoro- and hydrocarbon surfactants found in regular AFFF formulation, an Alcohol-Resistant (=AR) AFFF formulation contains a fluorochemical water-soluble but polar-solvent insolublexe2x80x94also referred to as xe2x80x9calcoholophobicxe2x80x9dxe2x80x94foam stabilizer (as described in this invention ) along with a polysaccharide such as xanthan gum. When these additives come in contact with a burning polar fuel fire, they precipitate and give rise to a membrane which protects the foam from dissolving in the polar solvent. This membrane creates a vapor barrier which extinguishes the fire and prevents reignition of the fuel along with keeping the foam hydrated. Polysaccharides and/or high molecular weight synthetic polymers may be used in AR-AFFF formulations without a fluorochemical foam stabilizer and provide the same efficacy. The problem with a foam concentrate containing only polysaccharides and/or high molecular weight synthetic polymers is that its viscosity is high and the concentrate behaves in a thixotropic manner. It is difficult to use a high viscosity foam concentrate since it is hard if not impossible to pump through a fire nozzle. AR-AFFF formulations containing fluorochemical foam stabilizers require much lower amounts of polysaccharides and/or high molecular weight synthetic polymers, thus lowering the viscosity of the foam concentrate. Additionally, foam concentrates containing fluorochemical foam stabilizers in AR-AFFF formulations tend to behave in a Newtonian manner.
Fire fighting foam stabilizers containing at least one perfluoroalkyl group and water solubilizing functionalities such as carboxy and amido groups are described in U.S. Pat. Nos.4,460,480 and in 5,218,021. French patent application 2637506-A describes an alcoholophobic and oleophobic fire extinguishing foam concentrate containing a polyhydroxy-polyamine containing at least one quaternary N atom and/or a polysaccharide which are chemically bonded to highly fluorinated C4-C20alkyl groups, instead of containing the fluorosurfactant separately and the polysaccharide or other alcoholophobic agent in the concentrated mixture.
Alcoholophobic fire fighting foam stabilizers containing at least one perfluoroalkyl group along with poly-quaternary amino and carboxy functionalities are described in world patents applications WO 9002110 A1 and WO 9003966 A1 along with publications by S. Szxc3x6nyi in Fire Safety Journal, 16, pp. 353-365 (1990) and Progress in Colloid and Polymer Science, 81, 136-139 (1990).
Since quaternary amino groups cause incompatibility with the anionic surfactants used in fire fighting formulations, further improvements have been described in WO 94/18245. This reference teaches compounds which contain a combination of at least two perfluoroalkyl groups, amino groups other than quaternary amino groups, carboxylic groups and other water-solubilizing groups attached to amino groups. For example, U.S. Pat No. 4,606,973 discloses aminoethylmethacrylate-acrylic acid copolymers in which the amino groups have been reacted with perfluoroalkyl carboxylic acids.
S. Szxc3x6nyi, Com. Journ. Com. Esp. Deterg., 22, pp. 297-304 (1991) describes a commercial state-of-the-art alcoholophobic foam stabilizer as a perfluoroalkylated polyamino acid.
An especially practical way to combine amino groups essential to foam stabilization with perfluoroalkyl-substituted compounds is to use readily available polyethyleneimine. The usefulness of polyethyleneimines in foam stabilizer formulations for polar solvent fires has been known for some time. For example, Japanese patent application S59-230566 describes useful foam stabilizers for polar solvents containing an anionic or amphoteric fluorosurfactant, polyethyleneimine of MW 4,000-100,000, and a polybasic acid compound.
U.S. Pat. No. 3,769,307 claims perfluoroalkylsubstituted polyethyleneimine compositions and the preparation thereof. This patent goes further to claim the use of such compounds as new textile finishes providing oleophobic properties. German Offenlegungsschrift 2 018 461 describes surface-active agents and foam stabilizers for polyurethane foams which are polyethyleneimines substituted by one or more perfluoroalkyl groups, as well as perfluoroalkyl-substituted polyamines containing up to 16 carboxy or sulfonic acid groups and/or hydrophilic amide groups. Although not directed toward foam stabilizer compounds for polar solvent fire fighting foams, the composition of this patent is described as very soluble in alcohol/water mixtures, but poorly soluble in alcohol (=xe2x80x9calcoholophobicxe2x80x9d) and water itself, making it a candidate for such foam stabilizers. Indeed, the above cited WO 94/18245 reference describes the synthesis of a perfluoroalkyl- and carboxy-substituted polyethyleneimine from tetraethylene-pentamine, a perfluoroalkyl acyl chloride and chloroacetic acid.
Japanese laid open patent application 59-164073 discloses reaction products of polyethyleneimine and anionic fluorinated surfactants, providing the acidic and fluorinated component for effective foam stabilizers on polar solvents.
World patent application WO 96/05889 A1 also describes foam stabilizers consisting of polyamines having perfluoroalkyl groups attached to the polyamine through ester linkages, and containing additional hydrophilic groups and optionally a non-perfluoroalkyl hydrophobic group.
Effective foam stabilizers on polar solvents have to be essentially insoluble in these solvents. They most commonly are poly-perfluoroalkyl-substituted polyamino acid compounds, such as those described above. The present invention discloses compounds useful as foam stabilizers for fire-fighting foams used on polar-solvent fires which are polyethyleneimine derivatives containing anionic and nonionic water-solubilizing groups, and further substituted with a mixture of perfluoroalkyl-allyloxy and perfluoroalkyl-iodopropyloxy groups or poly-perfluoroalkyl-fluoroallyl groups.
Mono-perfluoroalkyl (=RF) substituted amino acids have long been known to be excellent amphoteric surfactants, reducing the surface tension of water to as low as 16 dynes/cm. Such compounds, obtained by the reaction of an RF-ethylthiol, maleic anhydride and a di- tri- or tetra amine and containing up to two RF, carboxy- and amino groups are described for instance in U.S. Pat. Nos. 4,069,244 and 4,161,602. Di- and poly-RF-polyamino acids obtained by reaction of a di-RF-diol with a dianhydride and a diamine and containing 2-6 RF-groups, 4-10 carboxy and two tertiary amino groups are described in U.S. Pat. No. 4,153,590. These amphoteric compounds have been found useful as surface-active agents and film formers in aqueous and resin formulations.
Another class of amphoteric compounds with similar properties and also containing RF, acid and amino groups, and which are useful to impart oil repellency to paper products are di-RF-amino acids obtained by reaction of an amino acid, allyl glycidyl ether and RF-iodide as described in U.S. Pat. No. 5,491,261. This synthetic route, using an RF-iodide rather than an RF-thiol as the starting material, is more cost-effective, since it can be carried out in higher yields and produces much less waste.
It has now been discovered that by a similar route polymeric RF-amines, including polymeric RF-amino acids of the type which are useful as foam stabilizers for polar solvent fire-fighting foams, and which contain a plurality of RF groups as well as amino, and carboxy or other hydrophilic groups, can conveniently be prepared in similarly high yields and essentially without waste from a polymer containing a plurality of primary and/or secondary amino groups and a plurality of acid groups, by reaction with allyl glycidyl ether (=AGE) followed by addition of RF-iodide and partial dehydrohalogenation. The resulting mixture of poly-perfluoroalkyl-allyloxy- and poly-perfluoroalkyl-iodopropyl-substituted-polyamino acids are useful as grease-proofing agents for paper, but more importantly, they have been found to act as excellent foam stabilizers for Aqueous Fire-Fighting Foam (AFFF) formulations used on polar solvent fires.
Similar compounds, which are poly-perfluoroalkyl-fluoroallyl-substituted-polyamino acids and which are excellent foam stabilizers for AR-AFFF agents can be prepared by reaction of polyethyleneimines with a perfluoroalkylethyl iodide, followed by reaction with amino-reactive acid compounds such as chloroacetic acid or succinic anhydride. This reaction is believed to proceed through a perfluoroalkylethylene intermediate and subsequent elimination of HF, resulting in a 3-perfluoroalkyl-2-fluoro-allylamine structure. The addition reaction of perfluoroalkylethylenes to primary and secondary amines is described in U.S. Pat. Nos. 3,535,381 and 4,853,141.
It has also been found that the acid functionality is not essential to the performance of the compounds, but can be replaced by other hydrophilic groups, such as amide and/or hydroxy groups. Nonionically-substituted poly-RF-polyethyleneimines were furthermore found to give superior performance with saltwater; likewise, phosphoric acid-substituted poly-RF-polyethylene-imines were found to give superior performance with saltwater. Performance when mixed with saltwater is a major concern in firefighting operations aboard ships and in harbors.
The use of nonionically-substituted and phosphoric acid substituted poly-RF-polyethyleneimines as foam stabilizers in salt water fire-fighting foam formulations is thus another object of this invention.
The paper sizing chemicals and foam stabilizers of this invention are perfluoroalkyl-allyloxy- and perfluoroalkyl-iodopropyloxy-substituted polyaminoacids or poly-RF-fluoroallyl-substituted polyaminoacids which contain, in random distribution, q units of A-1, r units of A-2, s units of A-3 and t units of A-4 in which
A-1 and A-2 are perfluoroalkyl-substituted amino groups of the formulae 
A-3 is a hydrophilically substituted amino or amido group of the formula 
and A-4 is a substituted amino or amido group of the formula 
wherein
T is xe2x80x94CH2CH(OH)CH2xe2x80x94Oxe2x80x94CH2xe2x80x94 or a direct bond, with the proviso that
when T is xe2x80x94CH2CH(OH)CH2xe2x80x94Oxe2x80x94CH2xe2x80x94, QF is of the formulae
xe2x80x94CHIxe2x80x94CH2xe2x80x94RF (QF1) and xe2x80x94CHxe2x95x90CHxe2x80x94RF(QF2)
and consists of 5-50 mole % QF1 and 50-95 mole % QF2, and,
when T is a direct bond, QF, is
xe2x80x94CH2CHxe2x95x90CFxe2x80x94RFxe2x80x2xe2x80x83xe2x80x83(QF3),
q, r, s, and tare integers from zero to 100, the sum of q+r+s+t is 5 to 200, the sum of q+r is equal to or greater than 2, and the ratio of q+r/s is 0.1 to 2,
R is hydrogen or methyl,
RF is independently a monovalent perfluorinated alkyl or alkenyl, linear or branched organic radical having four to twenty fully fluorinated carbon atoms,
RFxe2x80x2 is independently a monovalent perfluorinated alkyl or alkenyl, linear or branched organic radical having three to nineteen fully fluorinated carbon atoms, with each RF and RFxe2x80x2 radical being identical or different from the other RF and RFxe2x80x2 radicals,
X is hydrogen, xe2x80x94CH2CH(OH)CH2xe2x80x94Oxe2x80x94CH2CHxe2x95x90CH2 or xe2x80x94Gxe2x80x94Y,
G is a direct bond or a linking group of the formula xe2x80x94CH2xe2x80x94, xe2x80x94CH2CHRxe2x80x94, xe2x80x94CH2xe2x80x94CH2C6H4xe2x80x94, xe2x80x94CH2CH2CH2xe2x80x94, xe2x80x94C6H4xe2x80x94, xe2x80x94CH(xe2x80x94COOH)CH2xe2x80x94, xe2x80x94CH2CH2CONHCH(OH)xe2x80x94, xe2x80x94COR1xe2x80x94, xe2x80x94CH2CHRCONHC(CH3)2(CH2)xe2x80x94, or a mixture thereof,
wherein R is as defined above,
R1 is xe2x80x94CHxe2x95x90CHxe2x80x94, xe2x80x94CH2CH2xe2x80x94, or xe2x80x94C6H4xe2x80x94 and
Y is an acid group of the formula xe2x80x94COOH, xe2x80x94SO3H, xe2x80x94PO3H2, or xe2x80x94(PO3H)3H, or a salt thereof, or is xe2x80x94CONH2 or xe2x80x94CH(OH)CH2OH, or a mixture of these groups,
R2 is an alkyl radical with 1 to 20 carbon atoms, or is xe2x80x94CH2CH2CON(CH3)2, xe2x80x94CH2CH2CONHCH2OH, xe2x80x94CH2CH2CON(CH2OH)2, xe2x80x94CH2CH2N(R4)2, xe2x80x94CH2CR1xe2x80x94COOR4 or xe2x80x94CH2CH(OH)CH2xe2x80x94Oxe2x80x94CH2CHxe2x95x90CH2, wherein
R4 is an alkyl radical with 1 to 18 carbon atoms or xe2x80x94CH2CH2xe2x80x94OH,
R3 is the same as R2 or is hydrogen, and R1 is defined as above.
Preferred are compounds as described above wherein QF consists of 10-40% QF1 and 60-90%
QF2, or is QF3,
RF is saturated and contains 6-12 carbon atoms, is fully fluorinated and contains at least one terminal perfluoromethyl group,
RFxe2x80x2 is saturated and contains 5-11 carbon atoms, is fully fluorinated and contains at least one terminal perfluoromethyl group
q+r is 2 to 20,
s is 5 to 80 and the ratio of q+r/s is 0.05 to 0.5,
t is 0 to 5,
R is hydrogen,
R2 is xe2x80x94CH2CH(OH)CH2xe2x80x94Oxe2x80x94CH2CHxe2x95x90CH2,
R3 is hydrogen or xe2x80x94CH2CH(OH)CH2xe2x80x94Oxe2x80x94CH2CHxe2x95x90CH2,
Y is as defined above and
G is a direct bond or is of the formula xe2x80x94CH2xe2x80x94, xe2x80x94CH2CH2xe2x80x94, xe2x80x94CH2CH2CONHCH(OH)xe2x80x94, xe2x80x94CH2xe2x80x94CH2C6H4xe2x80x94, xe2x80x94CH(xe2x80x94COOH)CHxe2x80x94 or xe2x80x94COR1xe2x80x94, where R1 is xe2x80x94CH2CH2xe2x80x94.
Particularly preferred are compounds as described above wherein QF, T, RF, RFxe2x80x2, q, r, s, t, R, R1, R2, and G are as defined above and Y is xe2x80x94COOH or xe2x80x94CONH2, with compounds wherein QF is QF1 and QF2 and consists of 10-40% QF1 and 60-90% QF2, T is xe2x80x94CH2CH(OH)CH2xe2x80x94Oxe2x80x94CH2xe2x80x94 and wherein G is xe2x80x94CH2xe2x80x94 and Y is xe2x80x94COOH being especially preferred.
Also especially preferred are compounds wherein QF is QF3, T is a direct bond, G is xe2x80x94CH2xe2x80x94 and Y is xe2x80x94COOH.
Also particularly preferred are compounds as described above wherein QF, T, RF, RFxe2x80x2, q, r, s, t, R, R1 and R2, are as defined above, G is xe2x80x94CH2CH2xe2x80x94 or xe2x80x94CH2xe2x80x94CH2C6H4xe2x80x94 and Y is xe2x80x94SO3H.
Also particularly preferred are compounds as described above wherein QF, T, RF, RFxe2x80x2, q, r, s, t, R, R1 and R2 are as defined above, G is xe2x80x94CH2CH2xe2x80x94 and Y is xe2x80x94PO3H.
Also particularly preferred are compounds as described above wherein QF, T, RF, RFxe2x80x2, q, r, s, t, R, R1 and R2 are as defined above, G is a direct bond and Y is xe2x80x94(PO3H)3H, xe2x80x94COOH or xe2x80x94CH(OH)CH2OH.
The novel poly-RF-(allyloxy/iodopropoxy) polyamines of this invention are obtained by first reacting allyl glycidyl ether with a part of the primary or secondary amino groups of a precursor polyamine polymer; then reacting this polyallyloxy-substituted polyamino prepolymer with an amino-reactive organic or inorganic acidic compound or other hydrophilic compound, and then reacting the product of this reaction with a perfluoroalkyl iodide.
The novel poly-RF-fluoroallyl-substituted polyaminoacids are obtained by reaction of a polyamine with a perfluoroalkylethyl iodide either before or after reaction with an amino-reactive acid or other hydrophilic compound. Due to the basic nature of the reaction medium, HI is eliminated and a perfluoroalkylethylene is formed as an intermediate, which adds to an amino group. During this reaction one equivalent of HF is eliminated; therefore the resulting perfluoroalkyl group (=QF3) contains one fewer xe2x80x94CF2xe2x80x94 unit than do the corresponding QF1, and QF2 groups.
The reaction is carried out in a high boiling polar solvent, preferably a glycol such as ethylene-, propylene- or hexylene-glycol at temperatures of 90-120xc2x0 C. over a period of three to twenty hours.
Useful amino-reactive acidic compounds are halogenated carboxylic or sulfonic acids or their salts of the formula Xxe2x80x2xe2x80x94Gxe2x80x94Y, which react by substitution of Xxe2x80x2, wherein Xxe2x80x2 is halogen, preferably chlorine or bromine and G and Y are defined as above. Preferred compounds are chloroacetic acid, chloropropionic acid and chlorosulfonic acid and their salts. Also suitable are vinyl unsaturated acids which react via a Michael addition reaction such as acrylic acid, itaconic acid, vinyl sulfonic acid and vinyl phosphonic acid, 2-acrylamido-2-methylpropane sulfonic acid and 2-acrylamido glycolic acid. Anhydrides which react by amide formation such as maleic-, succinic- or phthalic anhydrides, and sodium meta-triphosphate are also useful.
Useful amino-reactive non-ionic hydrophilic compounds are oxiranes and chloroacylamides such as glycidol and chloroacetamide.
The reaction of the polyallyloxy polyamino prepolymer with an amino-reactive organic or inorganic acidic compound or other hydrophilic compound proceeds readily at temperatures of 40 to 75xc2x0 C. The acids or acid salts can be added in a solvent, or preferably neat. Useful solvents are water and alcohols, such as n-propanol, 2-propanol and hexylene glycol.
Preferred reactants are xcex1-halo acids and their salts, with sodium chloroacetate being most preferred. Also preferred are xcex1,xcex2-unsaturated acids, with acrylic acid being most preferred. Also preferred are maleic- and succinic anhydrides and cyclic sodium meta-triphosphate, and mixtures of glycidol and chloroacetamide.
The reaction is carried out under either aqueous or anhydrous conditions, and the addition of a catalyst is not required.
These amino-reactive compounds can be used alone or in combination with each other. Alternatively, the amino-reactive hydrophilic compounds can be added to the polyamine before the addition of the ally glycidyl ether. In this case, a solvent is advantageously employed. Water is the preferred solvent. Allyl glycidyl ether is then added, preferably neat or in solution using a solvent such as propanol.
The final product is obtained by the reaction of a perfluoroalkyl iodide with the prepolymer in the presence of a free radical initiator such as an azo compound or peroxide at appropriate initiation temperatures, preferably at temperatures of between 50 and 80xc2x0 C. Sodium metabisulfite is preferably present to reduce iodine to iodide.
Solvents can be present; for example ketones such as acetone, methyl ethyl ketone or methyl propyl ketone or alcohols such as ethanol, propanol or butanol. If a solvent is used, it may be distilled off before dilution of the reaction mixture with water. The reaction is typically carried out over 4 to 10 hours at 50-80xc2x0 C. with good agitation. The resulting product mixture is diluted with sufficient deionized water to adjust the solids content to 15 to 40% by weight and the fluorine content to 4 to 10%.
Due to the basic nature of the reaction medium, much of the organic iodide is eliminated during the course of the reaction. The prepolymer is therefore obtained as a mixture having iodopropoxy and allyloxy linkages to the perfluoroalkyl moieties. If complete elimination of the organic iodide is desired, the addition of a strong inorganic base such as sodium or potassium hydroxide or a strong organic base such as 1,8-diazabicyclo(5.4.0)-undec-7-ene (DBU) is necessary.
It has further been found that the RF-I addition to the allyloxy groups can be carried out using sodium dithionite, at temperatures between 0 and 40xc2x0 C. Huang (Chin. J. Chem. 4, 350 and 358, (1990); Macromol Symp. 82, 67, 1994) teaches that the use of one equivalent of dithionite based on RF-I is necessary to add RF-I to terminally unsaturated compounds. It has been unexpectedly found that only 0.02 to 0.5 equivalents, preferably 0.05 to 0.2 equivalents, are sufficient to achieve essentially complete addition to an allyloxy-substituted polyaminoacid. An advantage of this process is that less color is produced and more organically bound iodine is retained. In addition the process can be carried out at higher aqueous dilutions. Carrying out the addition of RF-I to terminal double bonds in an aqueous solution containing 4-40% by weight of a water-soluble solvent such as a C1-C4 alcohol, an amide such as dimethylformamide, or a ketone at 0 to 40xc2x0 C., in the presence of 0.02 to 0.5 equivalents, preferably 0.05 to 0.2 equivalents, based on RF-I, of dithionite ion is thus another subject of this invention.
Useful polyamine starting materials have number average molecular weights ranging from about 200 to 10,000. They are typically polyalkyleneimines containing 4 to 300 primary, secondary and tertiary amino groups in ratios ranging from 1:1:0 to 1:2:1. Preferred are polyethyleneimines having molecular weights of 1000 to 5000. These polyamine starting materials are commercially available.
The following examples illustrate various embodiments of the invention, and are not to be interpreted as limiting the scope of the appended claims. In the examples, all parts are by weight unless otherwise specified. Perfluoroalkyl iodides CnF2n+1-I with n=4 to 14 were obtained from DuPont under the product names ZONYL(copyright) TELA-L and ZONYL(copyright) TELA-N . They have the following average telomer distributions:
ZONYL(copyright) TELA-L: C4=4% maximum, C6=50xc2x13%, C8=29xc2x12%, C10=11xc2x12%, C12=4xc2x11%, C14 and higher=2% maximum.
ZONYL(copyright) TELA-N: C6=6% max, C8=50xc2x13%, C10=29xc2x12%, C12=11xc2x11%, C14 and higher=4% maximum, respectively.
The corresponding perfluoroalkylethyl iodides, CnF2n+1xe2x80x94CH2CH2I, are available from DuPont under the product name ZONYL(copyright) TELB-L and TELB-N and have essentially the same telomer chain length distribution as TELA-L and -N.
When the compounds of this invention are used as oil proofing agents for paper, they are applied to the paper or paper board as an external coating by any conventional method such as padding, spraying or in a size press in amounts to deposit from 0.02 to 0.5% fluorine by weight on the paper. In addition to the fluorochemical, any of the conventional binders used in the paper industryxe2x80x94such as polymeric latex binders, carboxymethyl cellulose and polyvinyl alcoholxe2x80x94and sizing agents, such as ionic and nonionic starches like ethoxylated and oxidized starches, and water sizing agents such as alkyl-ketene-dimer (AKD) or alkyl-succinic anhydride (ASA) can be present.
In the following examples, external sizing application was accomplished using the following procedure: the products were applied to 34# waterleaf paper stock using a Werner Mathis laboratory padder in the horizontal mode. Samples were co-applied with 2% Penford 280 starch as sizing agent and Chel(copyright) DPTA 41 (from Ciba Specialty Chemicals Corp.) as a chelating agent in the standard manner. The paper was dried for 30 seconds on each side at 100xc2x0 C. using a photographic drier.
The oil repellency of a surface is determined by using the TAPPI UM 557 OIL KIT TEST. This test method consists of applying twelve different mixtures of castor oil/heptane/toluene having a surface tension range from 34.5 to 22.0 dynes/cm. The rating is based on penetration that occurs within 15 seconds of application; the ratings go from 1 (lowest), to 12.
As taught in column 2 of U.S. Pat. No. 5,496,475, the teachings of which are incorporated by reference, AFFF and AR-AFFF agents are generally sold in the form of liquid concentrates. These concentrates, which are rather complex mixtures (see column 7, lines 9-36), are diluted with fresh or salt water in proportioning equipment and sprayed onto a burning liquid as a foam.
The agents are usually sold as so-called xe2x80x9c3xc3x976xe2x80x9d and xe2x80x9c3xc3x973xe2x80x9d AR-AFFF concentrates, with the trend in the industry being toward the latter, where the numbers indicate the percent by weight of the concentrate contained in the diluted formulation for a fighting a fire involving a nonpolar fuel such as gasoline or a polar fuel, respectively.
When the inventive compounds are used as the foam stabilizer in an AR-AFFF agent, they are added to conventional AFFF and AR-AFFF formulations. The amount of the foam stabilizers typically used in 3xc3x973 AR-AFFF agents ranges from 1% to 4% by weight of the active ingredients. From 10 up to about 40% of the fluorine of the final formulation is thus derived from the foam stabilizer.
In order to test the efficacy of the novel foam stabilizers the following basic AR-AFFF formulation, free of any foam stabilizer, was used:
This mixture is referred to in the examples as AR-AFFF base.
Measurements of Foam Expansion Ratio (FXR) and Quarter Drain Time (QDT) were performed using the following procedure. A 3% solution of AR-AFFF was prepared in sea or tap water. The test solution was drawn into the calibrated liquid container by vacuum; see FIG. 1 below. The volume of the test solution was adjusted to 100 ml. The test solution was pressurized to 40 psi with compressed nitrogen. Compressed air was turned on and adjusted to 33 psi. The test solution was mixed with air at the mixing port before foaming at the nozzle. The volume of foam was measured in a 1000 ml graduated cylinder. The Foam Expansion Ratio of the foam was determined as the ratio of the total foam volume to the volume of the original test solution. Quarter Drain Time was measured as the time it took to collect 25 ml of drained liquid from the foam. Each test measurement was duplicated and the average was reported.
Foam Life on hot 2-Propanol was measured using the following procedure. A 3% solution of AR-AFFF was prepared in sea or tap water. The test solution was loaded in the calibrated liquid container by using vacuum, see FIG. 1 below. The volume of the test solution was adjusted to 75 ml. The test solution was pressurized to 40 psi with compressed nitrogen. Compressed air was turned on at 33 psi. The test solution was mixed with air at the mixing port before foaming at the nozzle. To a glass Pyrex pan 6.5 inchesxc3x9710 inches was added 250 ml of 2-propanol at 70xc2x0 C. The test solution was discharged as foam onto the hot 2-propanol and formed a blanket completely covering its surface. Foam Life was measured as the time it took for 50% of the foam area to collapse. Each test measurement was duplicated and the average was reported. 
Progress of the reaction of allyl glycidyl ether with polyethylenimine was followed by gas chromatography. The reaction was allowed to continue until allyl glycidyl ether was no longer detected.
ZONYL(copyright) TELA-L consumption was also followed by gas chromatography using an HP 5890 GC and a Supelco SPB-1, 60 mesh/0.53 mm by 3.0 m column with FID detector.
Determination of Ionic Chloride and Iodide was done by titration as described below: Equipment: Brinkmann Auto Titrator, Model E436; Fisher Ag/AgCl Reference Electrode; Fisher Silver Billet Indicating Electrode; Aldrich Standard AgCl. Procedure: 1) Weigh about a 0.2 g sample for chloride or 1.0 g for iodide into a 200 ml Beaker and dilute with 150 ml of water and add 1 ml of glacial acetic acid. 2) Titrate with 0.1023 M AgNO3 at 750 mv and a speed of xe2x80x9c2xe2x80x9d.             Calculation      ⁢              :            ⁢              xe2x80x83            ⁢      %      ⁢              xe2x80x83            ⁢      Conversion      ⁢              xe2x80x83            ⁢              (                  based          ⁢                      xe2x80x83                    ⁢          on          ⁢                      xe2x80x83                    ⁢                      Cl            -                          )              =                  ml        xc3x97        M        xc3x97                  (                      Total            ⁢                          xe2x80x83                        ⁢            R            xc3x97            n            ⁢                          xe2x80x83                        ⁢            Mass                    )                xc3x97        100        ⁢                  xe2x80x83                ⁢        %                              (                      g            ⁢                          xe2x80x83                        ⁢            sample                    )                ⁢                  xe2x80x83                ⁢                  (                      mmol            ⁢                          xe2x80x83                        ⁢            of            ⁢                          xe2x80x83                        ⁢            Chloroacetic            ⁢                          xe2x80x83                        ⁢            acid                    )                                %      ⁢              xe2x80x83            ⁢      Conversion      ⁢              xe2x80x83            ⁢              (                  based          ⁢                      xe2x80x83                    ⁢          on          ⁢                      xe2x80x83                    ⁢          I          ⁢                      -                          )              =                  ml        xc3x97        M        xc3x97                  (                      Total            ⁢                          xe2x80x83                        ⁢            R            xc3x97            n            ⁢                          xe2x80x83                        ⁢            Mass                    )                xc3x97        100        ⁢                  xe2x80x83                ⁢        %                              (                      g            ⁢                          xe2x80x83                        ⁢            sample                    )                ⁢                  xe2x80x83                ⁢                  (                      mmol            ⁢                          xe2x80x83                        ⁢            of            ⁢                          xe2x80x83                        ⁢                          R              F                        ⁢            I                              